JOHN AND Mary are affectionate newlyweds who want to swap genders. They visit Doctor Transit, a dwarf who has perfected a series of sex-change injections. The transition from female to male is rapid and exhilarating; the change from male to female takes longer and has a calming effect.

John becomes Joan, and Mary becomes Marlowe. The turnabout spouses remain married and in love; their new gonads function so well that Marlowe impregnates Joan. They decide that their forthcoming child will be male; if it's a girl, they'll ask Dr. Transit to correct the oversight. But after giving birth, Joan is homesick for her previous gender. Dr. Transit transforms Joan into an entirely new male named Jeremiah. Marlowe and the child discreetly fade out of the narrative.

Dr. Transit is murdered by a woman: apparently a genuine female, not one of his male clients. Jeremiah attempts to commit rape, then compiles a list of items that "in the absence of woman herself …fulfill the place of woman." Heading the list is "a square of paper." Jeremiah concludes that the perfect emblem of womanhood—"because of its headlong monotony of motion, in endless self-pursuit"—is the swastika.

This deeply misogynist transgender novel of 1925 discusses sexuality so frankly that the author was identified solely by initials. "I. S." was in fact Isidor Schneider (1896–1977), a Russian émigré who was active in the U.S. communist party, befriended the Hollywood Ten, and served in the Spanish Civil War.